


A Sexty Mistake

by wandering_revolve



Category: Big Hero 6 (2014)
Genre: Brotherly Angst, Dubious Consent, I'm Trying to Keep Things Somewhat Realistic, M/M, Masturbation, No Sex, Sexting, Sibling Incest, sorry about that
Language: English
Status: Completed
Published: 2016-10-15
Updated: 2016-10-15
Packaged: 2018-08-16 15:58:32
Rating: Mature
Warnings: Underage
Chapters: 1
Words: 3,975
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8108548
Author URL: https://archiveofourown.org/users/wandering_revolve/pseuds/wandering_revolve
Summary: A surprise text from Tadashi leaves Hiro reeling with new feelings.





	

Sixteen-year-old Hiro Hamada yawns while he sits at his computer. He decided against bot fighting tonight and researches robot prototypes instead. He scrolls through webpage after webpage and hardly stops to read a word. After a while, the black text runs together, and his eyes ache.

When an image finally catches his eye, he stares at it for a few seconds, figures he can build something better, and continues his journey down the page.

He jumps when his phone pings with a text message. A quick glance tells him it’s from his older brother Tadashi. Hiro’s not surprised. Tadashi always texts him whenever he plans on working late. Being the good little brother he is, Hiro always sends an “ok” back, just to let his brother know he received the message.

He unlocks his phone and goes over the text in his mind. Tadashi doesn’t use much word variation in his messages. However, when Hiro opens the message, it says something quite different than what he expected.

_U wanna take this for a ride? ;)_

Situated beneath the provocative text is a picture of a very long, very hard erection. Hiro’s jaw drops in complete shock. Tadashi, his fucking BROTHER, just sent him a dick pic! A strange feeling ties his gut into a knot, and he tosses the phone like it suddenly grew fangs and tried to bite him.

_What the FUCK?!_

He didn’t think Tadashi was that big…whoa, wait a minute. Why did that thought just cross his mind? He never once thought about what hides inside his brother’s pants. And for good reason. Well, now he knows, whether he ever wanted to or not. 

Hiro groans and holds his head in his hands. How he wishes he could unsee that picture. Why the hell would Tadashi send him that, anyways? Talk about the world’s nastiest prank. If that’s the case, there’s no way Hiro could top that one. He will hail Tadashi as the almighty prank king from now on.

His phone pings again, which nearly sends him to the floor in shock. His heart hammers in his chest as he looks down at his phone. Part of him doesn’t want to view the awaiting message. The other part, however, insists he should. With great hesitance, Hiro gets up and picks his phone back up. 

_Shit hiro, im so sorry! Please delete that!!_

Okay, so, Tadashi made a mistake – a rather horrifying one, at that. Hiro can’t help but wonder who the intended recipient was. He had no idea Tadashi is seeing someone. Then again, his brother is a very private person. He doesn’t just talk about what’s going on in his personal life. Hiro also had no idea his brother could be so…kinky.

Hiro doesn’t respond to the message. What’s the point? Maybe he can pretend like he never saw the picture. Tadashi might call bullshit, though, because he knows Hiro checks his phone whenever he texts him. 

Hiro brings up the Options menu and presses the Delete button. For some reason, he hesitates when the pop-up asks, “Are you sure?” and lets his thumb hover over the screen.

_“What the hell are you waiting for? Do I have to remind you that that’s your brother’s dick? You know how messed up you are if you save that picture? What if he finds out? We’re talkin’ years and years of therapy, bro.”_

Hiro manages to ignore his brain and exits the menu. Tadashi’s scandalous photo greets him, and he takes a good look at it this time. The perfectly round balls pop out of their dark, pubic nest. The shaft is thick but not too veiny. Precome is visible at the tip, thanks to the lab lighting. 

Hiro gulps when that strange feeling stirs up in his gut again. It takes him a moment to realize how hard his own member is. He actually got aroused from looking at a freaking picture of Tadashi’s most personal assets. Unbelievable.

T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H

A long masturbation session to his brother’s picture sends Hiro into a deep slumber. He didn’t have time to feel ashamed or question his morality when he felt that horny. He literally touched himself to the point of exhaustion, and his conflicted brain finally shut off for the night. He didn’t hear Tadashi return home, which is probably a good thing, even though he knows they can’t dance around the mistake forever. 

But he wishes they could. Especially when the very object of his fantasies sits across from him at breakfast the next day. The brothers avoid each other’s eyes. 

“Wow, you two are awfully quiet this morning,” Aunt Cass comments. She looks back and forth between them. “You guys okay?”

Tadashi swallows his mouthful of crepe. “Yeah, fine. Just got a lot on my mind with work.” He flashes her his usual smile.

Hiro’s heart skips a beat. It’s like he’s seeing that gorgeous smile for the first time. He didn’t realize he was staring at his brother until their eyes meet. Tadashi’s gaze flickers back down to his plate. Hiro does the same and takes a slow bite of food.

Aunt Cass shrugs. “Fair enough.” She turns to Hiro. “What’s your excuse?”

Hiro clears his throat and looks back up. “Just…inventions and stuff.” Yeah, he doesn’t lie as smoothly as his brother does.

“Inventions and stuff, huh? Okay, then.” Thankfully, she doesn’t question it further and rises from the table with her empty plate. “I wonder about you two sometimes.” She shakes her head with a fond smile and walks into the kitchen.

Hiro continues eating his breakfast in small bites. He really doesn’t feel hungry, but he forces himself to eat to make Aunt Cass happy. She gives them a hard time about wasting food. 

He chances a look across the table and notices Tadashi also slowed his eating down. He probably doesn’t have much of an appetite, either.

Guilt hits Hiro like a tidal wave. What kind of sick fuck takes advantage of their brother’s accidental dick pic like that? Tadashi feels humiliated enough. If he knew what his younger brother did last night, he’d pack up and move out. Nobody would blame him.

A call distracts Aunt Cass, and she leaves the room with her phone. Hiro immediately gets up and scrapes his remaining food into the garbage. His face heats up when he feels Tadashi's eyes on him.

“That’s a good idea.”

The deep voice sends chills up Hiro’s spine. He hears Tadashi’s chair squeak against the floor, followed by footsteps. The garbage bin sits beneath the sink, and Hiro stands there to wash his dishes. His breath catches at their proximity. Geez, maybe he really is coming down with something.

The younger doesn’t acknowledge the elder’s presence. Hiro dries his dishes with a rag as Tadashi leans against the counter with his arms folded.

“Hiro, I’m really sorry,” he mumbles.

Hiro doesn’t say anything. He returns the dishes to their proper places and turns to walk out. A hand on his arm stops him.

“Don’t leave. We need to talk about it.”

Hiro inwardly groans. He doesn’t want to do this, at least not now – not when he’s feeling so…strange.

“I’m sorry you had to see that.”

Hiro shrugs, trying to play it cool, despite the fact he’s overheating. “It was an accident.”

“A nightmare of an accident. I don’t know how we’ll recover from this.”

“I’m sure we’ll find a way.” 

Tadashi eyes him. “Why are you acting like it’s not a big deal? I ruined our relationship!”

“Who was it for?”

“What?”

Hiro rolls his eyes. “Ya know, the dick pic? Who were you supposed to send it to?”

Tadashi flushes. “That’s none of your business.”

Hiro scoffs. “You made it my business by sending it to me!”

“On accident!” Tadashi throws up his hands. “All right, fine, I’ve been seeing this guy, and-”

Hiro’s eyes widen. “Guy?”

“Yeah, and we sext sometimes. It’s not that big of a deal. A lot of people do it.”

“I know that, but I didn’t think _you_ were into that. And I didn’t know you were into guys. Or anybody, really.”

“I have urges and preferences like anybody else. I just don't like to talk about it."

Hiro smirks. “Talk about it then. What’s he like?” He pokes Tadashi’s arm teasingly.

Tadashi smiles bashfully. “I can show you a picture of him if you’d like.” He pulls out his phone.

Hiro shakes his head. “I think I’ve seen enough pictures for right now.”

Tadashi’s face darkens. “Let’s just…try to put this behind us, okay? I’m sorry it happened, and it definitely won’t happen again.”

“What if I want it to?” Hiro claps his hand over his mouth. Damn, where did that come from?

Tadashi blinks. “What?”

“Nothing!” he squeaks. “I, uh, I forgot I had something to work on.” He races upstairs, leaving Tadashi shaking his head after him.

T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H

Hiro flops down on his bed. He feels like he’s about to die, so he lies there and takes a few minutes to decompress. Yep, there is definitely something wrong with him. He probably played it a little too cool and got Tadashi all suspicious. What’s more, he almost blew his cover. 

He curses his brain for letting him say those words. That must’ve been attempted revenge for saving the dick pic. Speaking of the pic, he waits until he hears Tadashi leave for school before pulling it up on his phone. He stares at it and tries eliminating the connection with Tadashi. That should help him feel less guilty, right?

Hiro rolls onto his back and slides his pajama pants down. His member is already half-hard. He grips his growing erection in his right hand and his phone in his left. With the picture as his stimulus, it only takes a few strokes to reach full hardness. Hiro drops his jaw and moans quietly as he quickens his pace.

The image sears itself inside his brain. He imagines sitting down on that slick, hard length and taking it for a wild ride. Male anatomy has always excited Hiro, but, for some twisted reason, Tadashi’s anatomy takes that excitement to a whole new level.

With flushed cheeks and hitched breath, Hiro strokes himself in earnest. His hand glides along the pulsing shaft, and he teases the weeping head with each upstroke. A saliva-coated finger helps bring his body to a hot, messy climax, his brother's name lingering on his lips.

T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H

Hiro maintains this sneaky routine for a full two weeks. After breakfast, he retreats to the bedroom with the lie he’s working on something “big,” (which, in a sense, he is). He waits for Tadashi to leave before getting down to business.

The attempts to banish Tadashi from his mind were unsuccessful. How could he when everything Tadashi does and says suddenly became really attractive? His smile, his laugh, his walk, the way his face scrunches up in concentration, hell, even the way he _eats_ makes Hiro’s heart ache. That’s when he knew, with utter dread, that his fascination with an accidental dick pic turned into something much more serious.

Still, that didn’t stop him from beating it like an egg. Sometimes the guilt won, and he vomited in the bathroom. Other nights he cried himself to sleep. A vicious cycle of guilt and pleasure and something else he can’t identify consumes his adolescent life.

The thought he might get caught lingered in the back of his mind until the day it finally happened.

Hiro was in the heat of the moment when Tadashi barged into the room to retrieve a forgotten notebook. Hiro jumped and barely had time to cover himself with his sheets. Unfortunately, his phone flew out of his hand and landed on the floor screen-side up.

In the midst of Tadashi’s haste, the phone caught his eye, and he stopped in his tracks. At a turtle’s pace, he bent down and picked the phone up. Hiro covered his face with the sheets, his cheeks aflame with shame.

Tadashi stood there in the longest, most tense silence Hiro’s ever encountered. After what felt like forever, Tadashi exhaled. Hiro squeezed his eyes shut and braced himself for the lecture that was to come.

But it never did.

Instead, Tadashi tossed the phone back onto Hiro’s bed and left. When Hiro summoned the courage to peel away the covers, he checked his phone and saw no sign of the pic.

That all happened as recently as yesterday. The brothers haven’t spoken a word to each other since, and Tadashi opted to skip breakfast this morning. Aunt Cass didn’t approve, but he did it anyway and left early for school.

“What has gotten into that boy this morning?” Aunt Cass commented. 

Hiro knew but wisely chose not to respond. Now he sits curled up at his computer in an attempt to distract himself, although the weight of how badly he screwed things up with his brother, the one person he loves and admires so dearly, bears down on him like a freight train. If Tadashi thought the pic itself compromised their relationship, well, now there’s no doubt it will.

The day ceases to end. It drags on and on and on, and Hiro starts getting antsy. Part of him wants to hear from Tadashi, but the other part understands why he hasn’t. He doesn’t blame Tadashi for running from this. He can barely stand being around himself.

Day eventually turns into night, and Hiro still hasn’t heard anything. He wanders downstairs to ask Aunt Cass if Tadashi contacted her. To his relief, she says he’s at a sleepover.

But of course he is. Of course Tadashi doesn’t come home tonight of all nights. It only makes logical sense. Hiro contracted a sickness, and Tadashi doesn’t want to be around it. Simple as that.

T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H/T/H

After a fitful night, Hiro drags himself out of bed and trudges downstairs. Aunt Cass is busy creating awesome smells in the kitchen as usual, but Tadashi isn’t seated at the table, which is unusual.

Aunt Cass glances at Hiro while peeling pancakes off the griddle. “Sheesh, rough night?”

He yawns and sits down at the table. “Yeah.”

“Well, hopefully my apple-cinnamon pancakes perk ya up a bit.”

She sets a steaming plate of pancakes and eggs down in front of him. Hiro stares at the food and makes a face. It’s not that the food looks unappealing – he just lacks the appetite to eat it. However, out of courtesy, he forces himself to pick up his fork and dig in.

“’Dashi still not home?” he asks after a few mouthfuls.

Aunt Cass joins him with her own plate and shakes her head. “Nope, not yet. I haven’t heard anything from him since last night.”

“You think he’s okay?”

She shrugs. “He’s a smart kid. I trust he’s staying out of trouble…unlike you.” She flashes him a playful smile.

“Hey, I’ve been doing better lately.”

“I can’t argue with that. I’m glad you’re finding other ways to occupy the time.”

Hiro gulps down his bite of food too fast and almost chokes. Oh, if only she knew…

The compulsive urge to masturbate after breakfast disappeared along with the dick pic. Instead, Hiro hangs around and helps Aunt Cass clean up. It’s a welcoming change from the unhealthy routine. Besides, this gesture proves he’s still a good little nephew, what, since he lost the title of good little brother. 

When the clean up is almost complete, Tadashi stumbles in, looking like he got about as much sleep as Hiro did. His heavy eyelids try to hide the bloodshot eyes underneath, and his dark hair sticks up every which way.

“Morning, Tadashi,” Aunt Cass greets. “How was the sleepover?”

Tadashi gives a small shrug. “It was okay,” he rasps.

“I saved you a plate in case you’re hungry.”

“No, thanks, I’m fine. I’m gonna go take a nap.”

As to be expected, he doesn’t acknowledge Hiro and stumbles upstairs.

“Huh, looks like you both didn’t sleep very well,” Aunt Cass remarks.

Hiro yawns. “A nap does sound pretty good.”

He finishes putting away the dishes and retires to the shared bedroom. Tension smacks him in the face the moment he enters. Drawing in a deep breath, Hiro makes a beeline for his bed. He notices the divider closed further than usual, which is something Tadashi always does when he’s in a foul mood and doesn’t wish to be bothered. That’s okay with Hiro. They’ll just rest in the same space like they’ve always done. 

Hiro climbs into his bed, where he yawns again. He’s about to nestle into the sweet embrace of slumber when he hears a sniffle. His eyes fly open. Another sniffle follows right after, louder this time. Hiro sits up and glances at the divider. 

“Tadashi?” he asks carefully.

No response. With his heart pounding in his chest, Hiro gets up and wanders over to his brother’s side of the room. “Tadashi?” he repeats.

He hears a muffled sniffle, followed by a low, “Go away, Hiro.”

Hiro blinks. He can’t remember the last time Tadashi told him to leave. But, since he’s a stubborn little shit, he steps closer and peers around the divider. Tadashi lies curled on his side, facing away from him.

“Wanna talk about it?”

Tadashi doesn’t move. Hiro fights the instinct to rush to his despondent sibling’s side. On the other hand, he doesn’t want to make things worse than they already are, so he just stands at the opening.

“I’m so sorry,” he mumbles in a choked sob.

“Sorry for what?”

“Don’t be stupid, Hiro!” he snaps and falls silent again.

Hiro gulps and takes a step inside Tadashi’s personal space. He probably shouldn’t do this, but Tadashi isn’t stopping him. He stands at the foot of the bed. The elder Hamada covers his eyes with his arm.

“I really don’t want you to see me like this,” he mutters.

Hiro doesn’t respond. Instead, he takes a chance and sits down on the bed. Tadashi still doesn’t move, so he relaxes a bit.

“I’m sorry I kept the picture.”

Tadashi shakes his head. “It’s not your fault. None of this is your fault.” He sighs. “If I had just checked to make sure I sent that fucking text to the right fucking person, we wouldn’t be dealing with this right now.”

Hiro flinches at his brother’s harsh language. "Yeah, but I should've deleted it..."

Tadashi suddenly sits up and looks directly at him with an intensity Hiro’s never seen before. “Don’t you get it? You shouldn’t have seen it in the first place! I’ve fucked you up for life, Hiro, and I have to live with that!”

A stray tear rolls down his face, but he’s quick to wipe it away.

“Don’t blame yourself, ‘Dashi. We both made a mistake.”

Tadashi slumps back against his headboard, now avoiding Hiro’s eyes. “I guess so.”

They fall silent, until Hiro quietly asks, “So…where do we go from here?”

Their eyes meet again. Tadashi just stares at him thoughtfully before shaking his head. “I really don’t know. I can’t just say that we should forget about it and move on. This thing will keep haunting us. Maybe we should find a therapist? I don’t know.”

Hiro chews on his lip. He’s the one who needs therapy for his unbrotherly feelings. What happened on Tadashi’s end was just a tragic mistake.

“I’ll find a therapist for myself.” Tadashi quirks a brow. “I've...touched myself to your picture.” His cheeks darken.

Tadashi closes his eyes. “That's what I thought you were doing."

Shame settles hot and heavy in Hiro’s belly, and his eyes sting with tears. “I’m sorry I’m such a freak, ‘Dashi. I understand if you hate me and never wanna be around me again.”

Tadashi reopens his eyes and sits up straighter. “Hiro, you know I could never hate you, even after something like this.”

He crawls over to his younger brother and grasps the still baby-soft chin, forcing Hiro to look at him. Tears trail freely down Hiro’s cheeks.

“We’ll get this figured out, okay?”

Hiro sniffs and nods, his lip trembling. Tadashi’s thumb brushes the tears away, and his eyes flicker to Hiro’s mouth. Thin lips part to form a question when another pair of lips interrupt. Hiro’s body tenses, and his jaw would fall slack if it wasn’t for Tadashi’s hand holding his chin in place. As quick as the contact happens, it ends with Tadashi yanking back like he got burned. 

"Shit, Hiro, I-hmph!"

Without warning, Hiro crashes their lips together. The force knocks them back onto the bed. Hiro straddles the elder Hamada's waist and tries deepening the kiss. Tadashi grabs the teen's bony shoulders and pushes him away, breaking the contact. Hiro stares at him with an intense mixture of arousal, fear, and guilt.

Tadashi takes a few seconds to catch his breath. "Wow, okay, that's far enough."

Hiro sits back and wipes his damp eyes with his sleeve. "But...you kissed me first..."

Tadashi ignores the protest. "Let me up." He pats Hiro's legs.

Hiro's eyes narrow. "No." He stubbornly sits on Tadashi's legs. "You're not running this time, Tadashi."

Tadashi sighs in defeat. "I'm sorry, Hiro. What do you want me to say? I can't...I don't feel the same way you feel about me."

Hiro cocks his head to the side. "You still kissed me, whether it was an accident or not. That doesn't happen between brothers. We've already pushed the boundary. What's wrong with pushing it more?"

"Because doing stuff like this is wrong! We should stop it now before it goes further."

"And then what? Forget about it? You just said that we can't do that."

Tadashi chews on his lip. Hiro is really putting him into a difficult position. "What do you think we should do?"

Hiro lets his bangs fall into his eyes. "You don't wanna know..."

"Well, er, okay then." He pauses. "All right, here's the deal: I'll go along with this if it makes you happy. Hopefully this is just a temporary thing you're going through, but if you'd like us to be more...affectionate, then I'll allow kissing and cuddling. That's it. Don't ask for more, and don't expect more."

"Will kissing on the mouth be allowed?"

"Only if it's closed-mouth. And it's not making out."

"So, just one kiss at a time? That's kinda lame."

"We don't have to do anything at all."

Hiro blows out a breath, which ruffles his bangs. "Fine, okay, you got a deal." He rolls off of him and lies facing away from him.

"Hey, I said we could cuddle, remember?"

Hiro lifts his head and glances back at his brother. Tadashi wears a soft smile, his right arm extending away from his body. Slowly, Hiro accepts the invitation and sighs in contentment when Tadashi's strong arm wraps around his small frame.

"Can I have another kiss before I fall asleep?”

Tadashi nods, and their lips meet in a small, tender kiss. Being mindful of the rules, Hiro is the one who pulls away first this time. He yawns, rests his head on Tadashi's firm chest, and closes his eyes.

Tadashi cards his fingers through Hiro's shaggy locks. "The things I do for you, knucklehead," he mumbles before falling asleep with him.


End file.
